Analyses of woven hemp fabric characteristics for composite reinforcement

Abstract

The potential of plant fibres in composite material components can be enhanced by applying hemp fibres for fabrication of composites with aligned fibres. Fibre alignment can be enhanced by converting it into yarn. Applying fabric instead of yarn not only could enhance the fibre alignment but also could enhance the reinforcement handling during the composite fabrication. This paper presents a detailed characterisation of the woven hemp fabric. Two different batches of fabric with a similar quality were analysed to seek the difference between them. Both fabrics possessed similar physical properties as they were intentionally designed to have balanced properties in warp and weft direction. There was also a slight difference in their thermal behaviour but the differences between both fabrics allow their chemical compositions to be measured. These measured chemical compositions reflect their fibre density and mechanical properties. In terms of mechanical properties, their behaviours and properties were slightly different but via the inferential statistics, both fabrics were proven to have similar tensile strength and tensile modulus. The total cover factors for both fabrics were similar with 66% of fabric sheet that were covered by yarn and presumably could give good penetration of resin in composite fabrication. The findings of this study conclude that both woven hemp fabrics can be used and is suitable for composite reinforcement.

Full text

Analyses of woven hemp fabric characteristics for composite
reinforcement
M.I. Misnon
a,b
, M.M. Islam
a,
⇑
, J.A. Epaarachchi
a
, K.T. Lau
a
a
Centre of Excellence in Engineered Fibre Composites (CEEFC), Faculty of Health, Engineering and Sciences, University of Southern Queensland, Toowoomba,
Queensland 4350, Australia
b
Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia
article info
Article history:
Received 21 August 2014
Accepted 15 October 2014
Available online 20 October 2014
Keywords:
Hemp fabrics
Woven fibre properties
Mechanical properties
Chemical composition
abstract
The potential of plant fibres in composite material components can be enhanced by applying hemp fibres
for fabrication of composites with aligned fibres. Fibre alignment can be enhanced by converting it into
yarn. Applying fabric instead of yarn not only could enhance the fibre alignment but also could enhance
the reinforcement handling during the composite fabrication. This paper presents a detailed characterisa-
tion of the woven hemp fabric. Two different batches of fabric with a similar quality were analysed to
seek the difference between them. Both fabrics possessed similar physical properties as they were inten-
tionally designed to have balanced properties in warp and weft direction. There was also a slight differ-
ence in their thermal behaviour but the differences between both fabrics allow their chemical
compositions to be measured. These measured chemical compositions reflect their fibre density and
mechanical properties. In terms of mechanical properties, their behaviours and properties were slightly
different but via the inferential statistics, both fabrics were proven to have similar tensile strength and
tensile modulus. The total cover factors for both fabrics were similar with 66% of fabric sheet that were
covered by yarn and presumably could give good penetration of resin in composite fabrication. The find-
ings of this study conclude that both woven hemp fabrics can be used and is suitable for composite
reinforcement.
Ó2014 Elsevier Ltd. All rights reserved.
1. Introduction
Due to the growth of environmental awareness, the search for
new materials at affordable costs is highlighted. The focus has rap-
idly changed to develop, create and innovate eco-friendly materi-
als, which eventually introduced several new terms such as
renewable, sustainable and bio-based materials in material scien-
tists’ vocabulary [1–3]. The utilisation of natural fibres from plants
as reinforcements in composite materials is kind of remedy to fulfil
the new direction above. These kind of materials have existed for
quite some times and the current application of plant fibres in
composites is mainly for non-load bearing components in many
fields especially in the automotive and building industry [4–6].
This circumstance is primarily driven by lower price of natural
fibres, a demand of environmental awareness and to a lesser
extent, by the reinforcement effect of the natural fibres. Further-
more, its availability, complete data and sustainability seem prom-
ising to be used as raw materials [7].
Apparently, it is now the phase to entice industrial consider-
ation to the use of natural fibres in composite components as a nat-
ural alternative to the traditionally synthetic and man-made fibres.
One of the main problems is controlling over the fibre orientation
to ensure that the mechanical properties of the fibres are most effi-
ciently utilised and that the maximum fibre content is high. In the
textile industry, there are wide range of techniques to align plant
fibre including converting the natural fibres into yarn [4,8]. How-
ever, the established method of fabrication limits the usage of
yarns in composite application. Utilisation of textile fabric in com-
posite as reinforcement is well recognised for high-performance
fibres considering their advantages on high strength, good fibre
orientation and fibre distribution and more importantly easy to
handle during composite fabrication. In the case of natural woven
fabric, there is less work reported on their utilisation especially
when considering the type of natural fabric to be used as reinforce-
ment in composite material [3].
Not all of the natural fibres can be converted into fabric because
some of them can be considered new, and their extraction method
cannot produce fine and clean fibres. In order to convert the fibres
into woven fabric, fibres need to go through a long process from
http://dx.doi.org/10.1016/j.matdes.2014.10.037
0261-3069/Ó2014 Elsevier Ltd. All rights reserved.
⇑
Corresponding author. Tel.: +61 746311338; fax: +61 746312526.
E-mail address: Mainul.Islam@usq.edu.au (M.M. Islam).
Materials and Design 66 (2015) 82–92
Contents lists available at ScienceDirect
Materials and Design
journal homepage: www.elsevier.com/locate/matdes

spinning to weaving and this necessitates good, smooth and clean
fibres. Another method of producing fabric is by converting the
fibre into a non-woven fabric. However, its fibres are scattered,
bulky sheets, less flexible and possess lower mechanical properties
as compared to woven fabric [3].
Several fibres such as jute and hemp were established in woven
fabric and they possess good properties as reinforcement in com-
posite materials. However, their properties can be varied due to
different weathering conditions during plant growth and this fac-
tor cannot be controlled. Even in one quality of woven fabric pro-
duction, the raw materials (fibres) cannot be guaranteed to come
from similar source. This can create the variation in the fabric
properties that later could affect the composite properties. There-
fore, a study to characterise a different fabric batch in similar qual-
ity is needed to assess how far the differences in their properties.
There are few studies on the properties of natural woven fabric
for composite utilisation and many of them only relied on the
information given by the supplier. Therefore, in this study, the
properties of hemp fabric in two different batches with a similar
quality have been characterised with respect to; (i) fabric physical
properties, (ii) thermal and chemical composition analysis, (iii)
fibre density, (iv) fabric appearance structure, and (v) mechanical
properties. Statistical analysis, both in descriptive and inferential
using analysis of variance (ANOVA) in certain topic and section
depending on the priority were also conducted in order to seek
the significant differences between the average results and the
suitability of both fabrics in composite fabrication.
2. Material and method
Two (2) batches of commercial woven hemp fabric were inves-
tigated and supplied by Hemp Wholesale Australia. These batches
were bought with a time interval of about three (3) months.
According to the specifications provided by the supplier, the two
fabrics have equal nominal properties. The weight of fabrics is
271 g/m
2
and due to this it can be categorized as ‘heavy fabric’ in
textile term.
According to the specifications given by the supplier, the fabrics
were produced by 100% yarn hemp in both warp and weft with the
similar yarn linear density (yarn size) of 100 tex (g/1000 m) for
each direction respectively. The yarns were converted from
cleaned hemp fibre into yarn through spinning processes and the
twist given was 430 twists per meter. These yarns were then con-
verted into fabric via weaving processes and the fabrics were
woven by employing loose plain weave (taffeta) structure. Fig. 1
shows schematic diagram of plain weave fabric structure. As
referred to plan view, the vertical yarn is known as warp while
the other direction is weft. The plain weave structure can be cate-
gorized by observing the warp yarn which alternately and repeat-
edly goes over and under the weft yarn.
Other than that, the supplier did not give much data. Therefore,
further investigation was needed to characterise these two batches
hemp fabrics. For comparing purposes, the two batches of hemp
fabrics will be denoted as Fabric A and Fabric B (the batch bought
after three months). Fig. 2 shows the heavy weight 100% plain
woven hemp fabric used in this work.
2.1. Fabric characterisation
Woven hemp fabrics are characterised for their weight, thick-
ness, fabric density or fabric count while their yarn was character-
ised for its yarn size (linear density) and crimp (for warp and weft).
All tests have been done employing several textile materials stan-
dard methods. These standard methods are commonly used in tex-
tile industry for characterisation as well as product quality
determination purposes. Table 1 shows the standard methods used
to characterise both woven hemp fabrics.
Yarn spacing is normally related to the fabric compactness and
this could affect the fabric properties significantly. Yarn density in
fabric is generally known as ‘fabric density’ or ‘fabric count’. By
employing ASTM: D3775 standard method, fabric was placed on
a smooth surface and the number of warp and filling yarns were
counted using a pick counter in a 2 cm length and the result is pro-
nounced as; total warp yarn total weft yarn, per 2 cm.
Fabric weight was analysed in accordance to ASTM: D3776. Five
(5) specimens were needed for this analysis and three (3) readings
were taken from each specimen to get an average of fabric weight.
The weight was measured in gram per square meter (g/m
2
).
Fabric thickness was measured according to ASTM: D1777.
Twenty (20) randomly selected locations were used to obtain the
average value. This is to make sure the precision value which cov-
ers and represents the thickness of a sample since the sample is
hemp fabric which has a lot of thick and thin places. The thickness
values were taken in millimeter (mm).
ASTM: D3883 was used to measure yarn crimp. Parallel lines
were marked in the warp direction 20 cm apart (this is the distance
of the yarn in the fabric, Y1 = 20 cm). A cut of 30 cm was made
along the filling yarn, which crossed the parallel lines. Several
yarns from one edge were unraveled. The next ten (10) yarns were
carefully unravelled for measurement. Each yarn was pulled taut
without exerting extreme force and the extended length between
the two marks was measured as Y2. The yarn crimp, C, is calculated
as shown below in Eq. (1).
Plan view Cross-section
Fig. 1. The plain weave fabric structure in plan and cross-section views [9].Fig. 2. Woven hemp fabric used for this work.
M.I. Misnon et al. / Materials and Design 66 (2015) 82–92 83

Yarn crimp ð%Þ;C¼Y
2
Y1
1
Y1
1
100 ð1Þ
Yarn linear density was measured in accordance to ASTM:
D1907. Yarn was unravelled from the fabric and then cut to 1 m
length before it was weighed using a weighing balance. Ten spec-
imens were measured and the average weight, w, in grams, was
used for calculating the yarn linear density.
Yarn size ðtexÞ;N¼wk
lð2Þ
where lis the length of yarn in meter and kis the constant which
equals 1000 m/g for tex.
2.2. Thermogravimetric analysis
Thermogravimetric analysis (TGA) and differential thermo-
gravimetry (DTG) were carried out using thermal gravimetric ana-
lyser (TGA-Model No. Q500) at the temperature range from 24 to
600 °C with heating rate of 10 °C/min under nitrogen environment
purged at 20 ml/min.
2.3. Fibre density
The density of the hemp fibres was determined by
Multipycnometer MVP D160E. Helium gas was used as a
displacement medium. The helium was added to the fibres under
vacuum conditions to ensure that all interior air cavities in the
submerged fibres (e.g. the fibre lumen) were filled with helium.
The data reported are the average and standard deviation of
3 measurements.
2.4. Moisture content
Fabrics were conditioned at 65% R.H. and 23 °C for 24 h prior to
characterising their moisture content. Moisture content of the fab-
ric was determined by using Sartorius Moisture Analyser MA100/
MA50. This instrument will heat up the sample up to 105 °C. The
average value was calculated as follows;
Moisture content ð%Þ;M¼m
1
m
2
m
2

100 ð3Þ
where m
1
is initial weight of fabric and m
2
is the weight of fabric
after heating.
2.5. Mechanical properties
Tensile properties (ASTM: D 5034) of hemp fabrics were charac-
terised using universal testing machine MTS Alliance RT/10. 75 mm
wide test specimens were cut in the desired direction (warp or weft)
and then equal numbers of yarns were removed from both sides
until the specimen width was reduced to 50 mm. The same proce-
dure was followed for test strips in both warp and weft directions.
Tensile tests were performed using a gauge length of 75 mm and a
crosshead speed 2 mm/min. The cross-sectional area used to
convert load into stress was calculated from the test specimen
width and the thickness of fabric obtained from the fabric character-
isation [10,11].
Fig. 3 shows a typical tensile test curve for the hemp fabric used
in this work. According to Fig. 3(A), the initial part of the curve was
nonlinear but then increased its slope slowly until finally becoming
linear. The behaviour of the hemp fabric mechanical properties will
be further discussed in the Section 3.7. Other mechanical proper-
ties of this material cannot be determined under the nonlinear
curve. Hence, a linear trend line as shown in Fig. 3(B) was drawn
to extend the linear part of the curve to the axis of strain. With this
linear trend line extension, for each stress–strain curve, the tensile
modulus, tensile stress and strain at peak can be determined.
3. Results and discussion
3.1. Physical properties of woven hemp fabric
The determined physical properties of hemp fabric are pre-
sented in Table 2. No difference was found on the weaving struc-
ture for both fabrics. They are weaved in a perfect plain weave
similar to Fig. 1. When observing for fabric fault or defect, there
was no missing pick found along the fabric length for at least
5 m for both fabrics. Missing pick is referred to the defect in woven
fabric which can be detected by missing or out-of sequence yarn.
On the fabric, we can see an empty line throughout the width wise
of fabric and this defect is usually repeated in sequence in fabrics.
This is usually caused by loom (weaving machine) faulty due to
poor insertion of weft yarn. Fabric that has this defect will suffer
in inconsistent mechanical properties and poor fabric handling
especially in weft direction. Both fabrics tested are free from this
fault. Therefore, it can be concluded that all fabrics were manufac-
tured in good loom (most probably shuttleless loom) and they are
good-quality fabrics.
Table 1
Standard methods used to determine fabric properties.
Properties Testing Standard
method
Fabric density Warp (end) and filling (pick) count of woven
fabrics
ASTM: D3775
Fabric weight Mass per unit area (weight) of fabric ASTM: D3776
Fabric
thickness
Thickness of textile materials ASTM: D1777
Yarn size Yarn number (linear density) ASTM: D1907
Yarn crimp Yarn crimp and yarn take-up in woven fabrics ASTM: D3883
0
5
10
15
20
25
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14
Stress (MPa)
Strain
A
0
5
10
15
20
25
0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
Stress (MPa)
Strain
Linear trend line
B
Fig. 3. Typical curve of a stress–strain for hemp fabric: (A) is the whole complete
curve and (B) is a detail of the initial non-linear part.
84 M.I. Misnon et al. / Materials and Design 66 (2015) 82–92

Fabric density indicates the number of warp and weft yarns in
certain length of fabrics. Density of fabric can be used to indicate
yarn spacing and this could relate to the fabric compactness. The
distinctive in this property between two fabrics will relate to their
different fibre density in fabric and weight. In this works the mea-
surement was done in a metric system, which is centimeter (cm).
Based on the Table 2, both fabrics were determined to have similar
density that was 25 warps/2 cm and 23 wefts/2 cm (25 23/2 cm).
According to the specifications provided by the supplier, the
weight of fabric for both fabrics was similar which is 271 g/m
2
.
However, the measurement revealed that both fabrics, Fabric A
and Fabric B have different weight that was 231.41 g/m
2
and
228.52 g/m
2
respectively. The specification given by the supplier
was at least 17% higher than the measurement determined. There-
fore, further measurement on the fabric properties is needed to
gain accurate results. The thickness of Fabric A was recorded
0.4157 mm while for Fabric B a bit higher which was 0.4168 mm.
Yarn size or yarn linear density has a close relation with fabric
weight. Apart from measuring fabric weight, the density and com-
pactness can also be determined from this property. For that rea-
son, warp and weft yarn sizes for both fabrics were determined.
According to the supplier, the size of warp and weft yarns for the
woven hemp fabric is 100 tex. However, it was found that the
determined yarn sizes in both fabrics are at least 7% less than what
was mentioned by the supplier. From Table 2, Fabric A and Fabric B
possess similar weft yarn size, which was 93 tex. Nevertheless, in
the case of warp yarn, Fabric A possesses a bit smaller warp yarn
size in comparison with Fabric B, which were 89.661 and
90.459 tex respectively. Fabric B should be heavier as its weft yarn
size was measured higher than Fabric A, yet based on the result,
Fabric A is a bit higher than Fabric B. Again, further investigation
on the fabric properties is needed to obtained accurate results.
Yarn crimp is the waviness of the yarn in the fabric due to inter-
lacing of warp and weft yarns. It is well known that yarn crimp in a
woven fabric is an important parameter that affects most of its
physical properties and that include the thickness and the weight
of fabric [12]. Based on the results in Table 2, both fabrics have
similar weft crimp percentage, which is 9.3%. In terms of warp yarn
crimp, Fabric B has a bit higher crimp percentage than Fabric A
with the percentage of 6.0% and 5.4% respectively. Through obser-
vation on the warp crimp percentage for both fabrics, Fabric B has
longer warp yarn running on the longitudinal direction of fabric
than Fabric A. However, the crimp percentage does not support
the reason of heavier weight of the Fabric A since its warp yarn
crimp percentage is recorded lower.
3.2. Measurement of fabric weight
Based on the fabric specification given by the supplier, both fab-
rics should have similar aerial density or fabric weight of 271 g/m
2
.
However, the determined data obtained from the measurement
(Table 2) shows that Fabric A has higher weight (231.41 g/m
2
) than
Fabric B (228.52 g/m
2
). These figures are quite doubtful having said
that Fabric B possessed higher warp yarn crimp percentage and
warp yarn size while the weft yarn crimp percentage and weft yarn
size were identical.
Nevertheless, some other properties obtained from the mea-
surement such as fabric density, yarn size and yarn crimp percent-
age can be used to measure and determine the fabric weight
precisely [13]. The aerial density or fabric weight, W, can be mea-
sured using Eq. (4).
Fabric weight ðgk=m
2
Þ;W¼N
1
ð1þC
1
Þ
P
1
þN
2
ð1þC
2
Þ
P
2
ð4Þ
where Nis the yarn size calculated from Eq. (2),Cis the yarn crimp
percentage calculated from Eq. (1) while subscripts 1 and 2 refer to
warp and weft yarn respectively. Pis the yarn spacing in mm which
can be calculated from Eq. (5).
Yarn spacing ðmmÞ;P
n
¼t
dð5Þ
where subscript n= 1 or 2 which refer to warp or weft yarn, tis the
constant value of length for certain fabric density which is equal to
20 mm and dis the respective fabric density.
Results of fabric weight using Eq. (4) in Table 3 turns to give
more reliable readings with Fabric B was recorded higher in com-
parison with Fabric A which were 236.672 and 234.796 g/m
2
respectively. The higher weight possessed by Fabric B is consistent
with its higher yarn size and yarn crimp percentage. Therefore, the
calculation on fabric weight using Eq. (4) can be used to get reliable
and accurate results.
ASTM: D3776 is the standard method for measuring fabric
weight and it is normally used by fabric manufacturer, fabric mer-
chandise and buying officer. Nevertheless, error in fabric weight
measurement always happens and it usually is because of human
factor. The common error that might normally happen is when
preparing the sample before weight is taken. Without proper and
suitable equipment, testing officer could easily cut a fabric a bit
more or less and this could lead to inaccurate results. It is believed
that the uncertain results obtained when using this standard
method was due to the cutting error on the fabric sample thus
leads the Fabric A possess higher weight than the Fabric B. When
this happened, an accurate calculation measurement is needed
provided that the information of yarn size, yarn crimp percentage
and yarn spacing for both warp and weft yarn are given.
It is advisable when a fabric is meant for engineering applica-
tion, regardless of whether it is made of natural resources or
man-made, measurement on its fabric weight should be done by
using the calculation as in Eq. (4), which is more reliable and accu-
rate. This kind of measurement could eliminate the risk of getting
contaminated results from human error, reduce the employment
number of standard method as well as to save more fabric samples
in fabric characterisation analysis.
The results shown in Table 2 and also the results from fabric
measurement give an idea that both fabrics are designed as it
should be physically and mechanically balanced in warp and weft
direction. Even though it has the higher number of warp (25 yarns)
than weft yarn (23 yarns), the weft yarn is coarser (93 tex) than
warp yarn (90 tex). However, even it is designed to be mechani-
cally equal in warp and weft direction, other factors such as total
Table 2
Physical properties of woven hemp fabric.
Fabric types Fabric A Fabric B
Weave structure Plain Plain
Fabric density (per 2 cm) Warp 25 25
Weft 23 23
Fabric weight (Reading) (g/m
2
) 231.410 228.520
Thickness (mm) 0.415 0.417
Yarn size (Tex) Warp 89.661 90.459
Weft 92.896 92.970
Yarn crimp (%) Warp 5.4 6.0
Weft 9.3 9.3
Table 3
Results of fabric weight by calculation using Eq. (4).
Fabric types FSA10 A FSA10 B
Weight (g/m2) Total wt. of warp 118.083 119.813
Total wt. of weft 116.712 116.859
Fabric weight (g/m
2
) 234.796 236.672
M.I. Misnon et al. / Materials and Design 66 (2015) 82–92 85

weight of warp or weft yarn, and yarn crimp will result to a slight
difference in their mechanical properties. The difference in their
mechanical properties will be further discussed in Section 3.7.
3.3. Thermal analysis
Thermal analysis of woven hemp fabric sample was determined
using thermogravimetric analysis (TGA) and derivatives thermo-
gravimetric analysis (DTG) as shown in Fig. 4. The thermal stability
was studied in terms of weight loss as a function of temperature in
nitrogen atmosphere. From the curves, the decomposition of both
fabrics against increasing temperature was found a little different
in their behaviours. Based on the both DTG curves, the highest
mass loss rate for Fabric A was recorded higher than Fabric B which
was 1.51%/°C at 370 °C and 1.38%/°C at 380 °C respectively.
For Fabric A, the decomposition started from room temperature
(25 °C) up to about 120 °C with the weight loss percentage of
4.75%. The thing that happens here was the evaporation of
absorbed moisture in the fibres. The increase of temperature heat-
ing up the water molecule and made it migrated from the interior
to the surface of fibre. Therefore, the sample weight slightly
dropped in the initial process of heating [14].
Further decomposition happened with the 75.35% mass loss at
the temperature in between a 220 and 400 °C. This was due to
the degradation of hemicellulose and cellulose composition in
the hemp fibres [14]. At first, as the temperature increases, hemi-
cellulose is degraded due to the cellular breakdown and then fol-
lowed by cellulose at the higher temperature because it is highly
crystalline [15].
The sample continued to decompose from the temperature 400
up to 458 °C with the weight loss percentage of 3.52%. This is the
phase of lignin degradation after hemicellulose and cellulose. Lig-
nin is the toughest component and responsible for the rigidity of
the natural fibre. Thus, higher temperature is needed for lignin to
decompose. The Fabric A’s curve stopped at 458 °C and there was
still 15.64% mass remained. It was observed that the remaining
component was nothing but the ash content. This ash contains
inorganic material such as silica which can only degrade at a very
high-temperature [14].
As for Fabric B, there was no difference in behaviour as com-
pared to Fabric A. Initial reduction on the mass percentage was
4.26% which happened at the temperature of 25–120 °C was due
to evaporation of moisture content. Then, the degradation of hemi-
cellulose and cellulose happened at 220 up to 400 °C with the
weight loss percentage is lower than Fabric A which was 67.93%.
Another weight loss percentage happened in the phase of lignin
degradation with the value recorded a bit higher than Fabric A
which was 5.80% at the temperature of 400–458 °C. Fabric B has
higher ash content with the amount recorded 22%.
3.4. Chemical composition of hemp fabric
Chemical composition of woven hemp fabrics was determined
by using TGA analysis and estimation based on the pyrolysis study.
Generally, there are four phases of thermal decomposition for
natural or plant fibres. These phases are; moisture evaporation, fol-
lowed by hemicellulose decomposition, cellulose, lignin and lastly
their ash [14]. Results obtained by Yang et al. [15] on the natural
material pyrolysis can be used as a benchmark for estimating the
chemical composition of woven hemp fabric in this work.
The degradation of hemicellulose start at 220 °C and finished at
315 °C yet they produce 20% or solid residue. Hemicellulose con-
sists of various saccharides appear as random amorphous structure
and rich in branches which is easy to decompose at a lower tem-
perature. The cellulose decomposes at a higher temperature range
(315–400 °C) and produces fewer residues than hemicellulose,
which is 6.5%. Cellulose does not start to decompose until hemicel-
lulose has completely decomposed. The reason for this is because
cellulose has a high crystalline chain in their structure than amor-
phous thus makes it relatively thermally stable. Lignin decomposes
at wide temperature range starting from 160 to 900 °C. Lignin is a
tough component that gives rigidity to the plant material and pro-
viding rigidity to the cell wall by becoming a binder to individual
cells in the middle lamella region. That is the reason why the lignin
is difficult to decompose at the lower temperature [15]. This work
can be said accurate involving pure hemicellulose, cellulose and
lignin compound.
Based on the pyrolysis work above, the chemical composition of
hemp fabric can be estimated using its TGA curves. Five composi-
tions value can be obtained were moisture or water content,
hemicellulose, cellulose, lignin and ash. Their content can be deter-
mined by measuring the weight loss percentage at the certain
range of temperature from pyrolysis work by Yang et al. [15].
Table 4 presents the determined chemical composition of woven
hemp fabric using estimation method.
Moisture content of woven hemp fabric can be easily measured
from the weight loss percentage from the TGA curves because it is
the first phase of thermal decomposition of natural plant. In order
to verify the results in Table 4, content of moisture for both hemp
fabrics were measured by using Sartorius Moisture Analyser
MA100/MA50. This equipment measures the different weight of
hemp fabric before and after heating. While, the result of moisture
-0.5
0
0.5
1
1.5
2
0
20
40
60
80
100
0 40 80 120 160 200 240 280 320 360 400 440 480 520
Mass loss rate (%/°C)
Mass (wt. %)
Temperature (°C)
Fabric A
Fabric B
Fig. 4. TGA and DTG curves of woven hemp fabric.
86 M.I. Misnon et al. / Materials and Design 66 (2015) 82–92

content for Fabric A and B using this equipment were 4.75% and
4.42% respectively, the results measured from the TGA curves for
both fabrics were determined as 4.91% for Fabric A and 4.31% for
Fabric B. The results between two methods are said comparable
and the slight difference between them is most probably due to
the effect of the different environment temperature and humidity
when the tests are done.
Fabric A has higher hemicellulose content in comparison with
Fabric B which was 8.46% and 5.95% respectively. These figures
are comparable with the results obtained by several other workers
[4,16,17]. Since there is no information given by the supplier, the
differences in value between two fabrics is most probably due to
the chemical treatments given by the hemp fabric manufacturer.
It is well known that sodium hydroxide (NaOH) is the common
chemical used not only in the yarn processing but also in weaving
preparation process and its usage can be as high as 30% w/w. Kabir
et al. [16] in his work found that the hemicellulose content reduced
(5.40–4.51%) as the concentration of alkali treatment increased
(0–10% w/w). Therefore, it can be said that the difference in hemi-
cellulose content in Fabric A and B is most probably due to the
chemical treatment on both fabrics during their manufacturing.
The highest component is cellulose and it is the main constitu-
ent in any plant fibre. Cellulose content in Fabric A (67.47%) was
recorded a slightly higher than Fabric B (64.77%). The figures are
comparable and within the results determined by other works
[16,18–21]. Since cellulose is a compound that is least affected
from the chemical treatment, the difference in percentages of cel-
lulose contents for both fabrics is insignificant [22,23]. Lignin con-
tent in Fabric A and Fabric B were determined at the temperature
of 400–458 °C, where the burning was completed and the results
were recorded as 3.52% and 2.92% respectively. Again, similar rea-
son with hemicellulose, the lower content of lignin for both fabrics
is most probably due to the chemical treatment used during their
manufacturing. Sedan et al. [24] in his work presented hemicellu-
lose and lignin content percentage which are 10.9% and 6% respec-
tively. The lignin composition in his work is high in comparison
with the lignin composition in this work and his higher value is
possible since he used the hemp in the fibre forms instead of
woven fabric. Extracted hemp fibre is the raw material of hemp
product before it is converted into other forms of material. There-
fore, hemp fibre did not go through lots of chemical processes as
compared to hemp fabric which has gone through many chemical
processes such as in spinning (conversion of fibre into yarn) as well
as in weaving (conversion of yarn into cloth).
The ash content for Fabric A and Fabric B were measured as
15.64% and 22.05% respectively. Ash is the component that con-
tained inorganic material such as silica and can only be decom-
posed at a very high temperature [14]. Therefore, the higher ash
content in the Fabric B is associated to the fabric containing higher
inorganic material than Fabric A. Nevertheless, this ash content do
not affects mechanical properties because the fibre is most affected
by the contents of hemicellulose, cellulose and lignin [3,25].
3.5. Density of fibre
The density of fibre for Fabric A and B determined by pycnom-
etry are presented in Table 5. Each series of measurements consist
of two specimens and three reading was taken for each fabric. The
results show that for each series of measurements, the fibre den-
sity is higher for Fabric A than Fabric B with overall means of
1.512 and 1.473 g/cm
3
respectively. The determined density of
the hemp fabric fibres is comparable and within the typically
reported densities of hemp fibres varying between 1.4 and
1.5 g/cm
3
[3,26].
The small difference in their density is due to the measured
slightly higher cellulose content in Fabric A than Fabric B (see
Table 4). According to Madsen et al. [4], the density of hemp fibre
can vary depending on how much the cellulose content in the
fibres. When analysing the results obtained in his work as well
as comparing with the results of other workers, he concluded that
the increase of cellulose content in the fibre, can lead to a higher
density of the fibre. In his work, the determined fibre density
was much higher which was in the range of 1.58–1.60 g/cm
3
with
the determined cellulose content was in the range of 88–90% [4].
Therefore, the determined average density of hemp fibre in this
work is relevant with the measured cellulose contents of both fab-
rics and the results’ trend follow the trend obtained by Madsen
et al. [4].
3.6. Fabric appearance structure
Fig. 5 shows the appearance structure of woven hemp fabrics. It
was observed that the weave structure of both fabrics were plain/
taffeta weave structure. This is the most basic woven structure
other than twill and satin. Most woven fabrics are used for techni-
cal purposes are manufactured with plain weave structure. Apart
from easy to produce, it reduces the cost of production as well as
downtime of the loom thus increases productivity [9]. Other weave
structures are more complex and the arrangement of yarns is more
complicated that could lead the yarn breakage due to the friction
between the yarns in the loom.
When observing the structure of hemp fabric, the yarns were
not homogenous entities but were varying in cross-sectional
dimensions. It can be shown in Fig. 5 that there are lots of thick
and thin yarns found running in the warp and weft directions.
The yarns size determined for both fabrics are just the average val-
ues (refer Table 2). Since the fabrics used are made of natural
fibres, this kind of irregularities and inconsistencies with the yarn
were expected to happen. Yarn is produced in the long production
line called ‘spinning’. In the spinning process, there are a lot of
drawing processes purposely to get the required yarn size. How-
ever, even with perfect drawing, the irregularities still happen
because natural fibres are usually short and it is difficult to control
the total fibre along the yarn [3]. The yarns for both fabrics were
observed to have twists with a right-handed angle to the yarn axis.
This twist is also known as Z-twist in contrast to S-twist. According
to the supplier, all the yarns for both fabrics either warp or weft
has been spun with 430 twists per meter. Since the focus of this
work is on the fabric rather than yarns, and the twist angles defi-
nitely will be varied slightly because of the nature of spun natural
yarns, this twist value is received as specified by the supplier. More
importantly, the properties related to the fabric appearance should
be emphasised.
Table 4
Chemical compositions of woven hemp fabrics.
Hemp fabric types Fabric A Fabric B
Composition (%) Moisture 4.91 4.31
Hemicellulose 8.46 5.95
Cellulose 67.47 64.77
Lignin 3.52 2.92
Ash 15.64 22.05
Table 5
Density of fibre (g/cm
3
) of the Fabric A and B determined by 3 series of
measurements.
Fabric types Series of measurement
I II III Average Stdv.
Fabric A 1.528 1.499 1.510 1.512 0.015
Fabric B 1.481 1.472 1.466 1.473 0.007
M.I. Misnon et al. / Materials and Design 66 (2015) 82–92 87

Fabric cover factor indicated the extent to which the area is cov-
ered by one set of yarns. This is an important criterion, which
relates to fabric applications, for instant, how is the level of shade
for a fabric to be used as a shading material or how good the pen-
etration of resin if certain textile fabric is used as a reinforcement.
In order to determine total fabric cover factor, a modified equation
(Eq. (6)) introduced by Chen and Leaf [13] was used and the Kvalue
is the ratio on how big the area is covered by the yarns.
Total fabric cover;K¼C
1
þC
2
C
1
C
2
ð6Þ
where subscripts 1 and 2 are referring to warp and weft yarn
respectively and Cis the fractional yarn cover which can be calcu-
lated from Eq. (7).
Fractional yarns cover;C
n
¼sffiffiffiffiffiffiffiffi
ðN
n
p=f
d
Þd
n
10
3
ð7Þ
where subscript n= 1 or 2 which refer to warp or weft yarn, sis the
constant which is equal to 4.44, Nis the yarn size calculated from
Eq. (2),f
d
is the fibre density (refer Table 5) and dis the respective
fabric density.
The results of cover factor are tabulated in the Table 6 and there
are no differences between Fabric A and Fabric B. The results
clearly show that for both fabrics, 66% (0.66) of the fabric sheets
are therefore covered by yarn. The slight differences between them
are most probably due to the mechanical variations which
occurred on loom during their production. From the textile point
of view, both fabrics share identical cover factor quality and can
be used in a similar batch of textile product for certain application.
The effect of water penetration and air permeability should be also
comparable for both fabrics. The yarns only cover 66% of fabric
sheet, that means the water and air will easily penetrate or pass
through the fabric. In composite fabrication, the good penetration
of resin into the whole fabric system is expected. Nevertheless,
in terms of technical applications, the physical, chemical and
appearance properties of fabric are inadequate for a fabric used
in the technical applications. Therefore, assessments on their
mechanical properties are more crucial to study on how well their
response to the external force is given on them.
3.7. Mechanical properties
Typical stress–strain curve of woven hemp fabric is shown in
Fig. 3(A). Study on the behaviour of woven hemp fabric in this
work can be clustered in three phases. The first phase is the initial
region that demonstrates a curve with a low slope. Second phase is
the linear region of the curve after the fabric settlement, which
rises steeply until its summit is reached and the third phase is
the curve after it reaches the peak.
In the initial phase, the curve rose with a low slope due to decr-
imping and crimp interchange. The decrimping and crimp inter-
change is internal interaction (crossover between warp and weft
yarns) of a fabric that results to the initial curve. When a woven
hemp fabric is extended in either of principal directions, a straight-
ening of the crimped yarns occurred in the direction of force. In the
direction of force, the yarns appear to become less flattened due to
the consolidation into more circular cross-section. As the pressure
builds up for the yarn in the direction of force, the continuous
interchange between two yarns also happened simultaneously
thus increases the crimp in the yarn perpendicular to the force
direction.
Yarns in the direction to force will continuously become round
and less flattened as the fabric is further extended. Here, yarn and
fibre extensions will occur, but the yarn extension only accounts
for a small portion as compared to the extension of yarn in the first
phase. The small extension of yarn in here suggests that the inter-
action between the fibres due to the twist give to the yarn become
tighter and stronger and create a build in pressure for the yarn to
resist tensioning force. The internal interaction still happened,
but the contribution of the perpendicular yarns against the force
direction is just small. This behaviour is shown in the second phase
in which the stress–strain curve increased sharply until it reaches
the peak and then breaks.
Fig. 6 shows the tensile stress–strain response for both Fabric A
and B. For each type of fabric, specimens were cut and tested in the
warp and weft direction. Table 7 summarizes the average tensile
properties for each woven hemp fabric. The tensile properties
reported are the average and standard deviation from all the spec-
imens. The curves are cut off at the point of ultimate stress. For
every type of fabric, the curves are clearly divided into two groups
represented by the warp and weft yarns.
In the case of Fabric A (Fig. 6), the initial curves were risen with
a low slope due to decrimping and crimp interchange of fabric. This
state was observed longer for weft direction due to higher crimp
percentage it possessed (9.3%) in comparison with warp direction
(5.4%). Therefore, it took more time for weft yarn to be straight-
ened, and most of the weft specimens had reached their settlement
state at approximately 0.07 strains while for warp specimens were
recorded about 0.03. After the decrimping and crimping state at
initial stage, the curves for both fabrics rose steeply until their
peaks were reached. The wefts failures were observed mostly at
higher stress than warps yarn. The higher yarn crimp percentage
of wefts is the reason why it could fail at higher stress than warp
on top of the higher yarn size it possessed (93 tex for weft and
90 tex for warp).
The curves risen consistently from the beginning, yet the
greater variation is noticeable near failures because failure likely
initiates at thinner yarn places (Fig. 7) which scattered along the
fabric specimens [27,28].Fig. 7(a) shows an example of a specimen
after subjected to tensile force. From the figure, it is clearly shown
that the yarn fractures are scattered along the fabric specimen and
most likely to break at thin places. Fig. 7(b) shows a magnified yarn
fractures area on the fabrics. It was observed that the fractures
Thin yarn
Thick yarn
Fig. 5. The structure of woven hemp fabric.
Table 6
Result of cover factor for both fabric used in this work.
Fabric types Fractional yarn cover Total fabric cover
Warp C1 Weft C2 K
Fabric A 0.435 0.406 0.664
Fabric B 0.433 0.405 0.663
88 M.I. Misnon et al. / Materials and Design 66 (2015) 82–92

happened mainly at the area that has many thin yarns. There were
many pulled-out fibres found at the fractured yarns that suggest
the fibres were resisting the tensile force acting on them.
There are not so much difference in the stress–strain behaviour
for Fabric B (Fig. 6) in comparison with Fabric A. Even their speci-
mens’ curve started to reach the linear part at similar strain. This is
because the strength of warp and weft yarn for both fabrics is quite
similar (refer Table 2). The slight difference between the speci-
men’s behaviour is due to the variation in the fabric such as yarn
irregularities and thick-thin places. Therefore, it can be said that
both fabrics share similar behaviour in stress–strain.
The results of tensile properties for both woven hemp fabric are
shown in Table 7. The figures in the table are the average ± stan-
dard deviation for at least 9 specimens. Overall, it can be said that
the tensile strength of Fabric A is higher than Fabric B. In terms of
warp direction, tensile strength of Fabric B was recorded 6% lesser
than Fabric A which was 24.883 and 26.304 MPa respectively. The
similar trend was found in the weft direction specimens with the
tensile strength of Fabric B was determined as 21.975 MPa, 6.4%
lower than Fabric A which was 23.392 MPa.
When the fabric is fully stretched, that is after the decrimping
process at internal interchange (refer to Fig. 6), the yarns have
now become straight and round. The acting tensile force on the
fabric is now divided and separated on the yarns in the force direc-
tion (either warp or weft) and it is against the builds up pressure
from each yarn. The builds up pressure exists due to the interaction
of fibres in the yarns effect from the twist given to them which
resisting the tensile force. How great the yarns can resist the force
acting on them depends on how much twist is given to the yarn
because the twist is the reason why the fibres entangle with each
other in a yarn [29]. In the normal practice, the higher the amount
of twists given to them, the higher builds up pressure in the yarn
can be produced (for both fabrics, warp and weft yarns were spun
with 430 twists per meter). Other factors that contribute to the
builds up pressures in the yarns are fibre length, total fibres, fibre
density and linear density (yarn size). All the factors are then com-
bined in a fabric the builds up pressure is accumulated to against
the tensile force.
Another factor that contributes to the strength of the fibres in
the fabric is the cellulose content. Cellulose is the compound in
the natural fibre that is responsible to give the strength. According
to Azwa et al. [23] tensile strength and Young’s modulus increases
as the cellulose content increased. Based on Table 7, the tensile
strength of warp and weft yarns for Fabric A were determined
higher than Fabric B. This is consistent with the higher cellulose
content in Fabric A than Fabric B with the overall content of
67.47% and 64.77% respectively (refer Table 4).
Tensile strain of Fabric B in warp direction was determined 20%
higher than Fabric A which is 0.093 and 0.074 respectively. As for
weft direction, Fabric A was found to be slightly higher (7%) than
Fabric B with overall results of 0.121 and 0.112 respectively. The
higher strain in weft direction for both fabrics is due to the higher
crimp of weft yarn in the fabrics that is 9.3%. The longer strain in
warp direction for Fabric B is because of the higher crimp percent-
age, which is 6.0% as compared to Fabric A, which is 5.4% (refer
Table 2).
Similar trend with tensile strength was observed for tensile
modulus. For Fabric A, tensile modulus was recorded 2% higher
than Fabric B with average value of 0.54 and 0.53 respectively. In
weft direction, tensile modulus of Fabric B was recorded
0.493 GPa, 3.7% lower than Fabric A (0.511 GPa). Overall, it can
be concluded that tensile modulus for warp was found higher than
weft direction for both fabrics. Although the yarn size for weft
direction was measured higher than warp direction, the higher
density of yarn (fabric density) was found in the warp direction
for both fabrics which is 23 and 25 for weft and warp respectively
(refer Table 2). This is the reason why the tensile modulus is
slightly higher in warp direction. When comparing both fabrics,
Fabric A can be said to have higher tensile modulus than Fabric B
due to the higher lignin content in its composition than Fabric B.
Apart of cellulose contribution to the fibre stiffness, lignin is the
compound that is most responsible on the fibre stiffness. Lignin
is a complex hydrocarbon that gives rigidity to a plant and it is
functioned as a matrix for cellulose fibrils in fibres [14,15,23]. That
is the reason of the higher tensile stiffness for Fabric A in compar-
ison with Fabric B.
Tabulated data in Table 7 cannot be used to accurately deter-
mine the significant difference between the average values
because of the variation of raw data to their mean/average. There-
fore, an inferential statistic should be applied in order to test signif-
icant difference between the mean values. The results come from
inferential are more valuable especially for the manufacturers to
decide the suitable material to be used in their production and
design. An analysis of variance (ANOVA) was conducted using
0
5
10
15
20
25
30
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
Stress (MPa)
Strain
Fabric A
-Warp
- We
0
5
10
15
20
25
30
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
Stress (MPa)
Strain
Fabric B
-Warp
- We
Fig. 6. Tensile stress–strain response for Fabrics A and B.
Table 7
Summary of average tensile properties for woven hemp fabrics.
Fabric types Peak load (N) Tensile strength (MPa) Tensile strain Tensile modulus (GPa)
Fabric A Warp 442.1 ± 29 23.392 ± 1.52 0.074 ± 0.004 0.540 ± 0.023
Weft 497.5 ± 56 26.304 ± 2.99 0.121 ± 0.008 0.511 ± 0.032
Fabric B Warp 415.3 ± 21 21.975 ± 1.11 0.093 ± 0.026 0.530 ± 0.041
Weft 469.3 ± 38 24.833 ± 1.99 0.112 ± 0.006 0.493 ± 0.044
M.I. Misnon et al. / Materials and Design 66 (2015) 82–92 89

IBM
Ò
SPSS
Ò
Statistics version 21 was used to test the significant
difference between all samples in this work. ANOVA use F distribu-
tion that compared three or more population means to determine
whether all the populations or samples are equal. Take tensile
strength in Table 8 as an example; in this case, ‘sum of squares’
is the sum of the squared deviation of tensile strength. The ‘df’ is
degree of freedom, which is used to obtain the observed of signif-
icance level. ‘Mean square’ is the sum of square divided by degree
of freedom. ‘F’ is the ratio of two means square, which is used to
test the null hypothesis that can be rejected if the significance is
small at the P-level (P-level is also similar with Sig. in the Duncan
test) of 0.05 or 0.01. This Table 8 is originally provided and auto-
matically calculated by SPSS. The concern here however, is the
focus on the column ‘Sig. = 0.000’ which means there is a signifi-
cant difference between the materials and if the value is more than
0.05, that means the different is ‘insignificant’ or ‘not significant’.
The results of ANOVA in the Table 8 shows that for tensile
strength and tensile strain, there is a significant difference among
the warp and weft yarns directions of hemp fabric considering the
significant value (Sig.) were all 0.000. In the case of tensile modu-
lus, the significant value was recorded 0.034, which is also lower
than 0.05 indicating that there is a significant difference among
the groups. In order to extent the analysis in Table 8, ANOVA post
hoc multiple comparison tests employing Duncan was also used to
(a) (b)
Fractured yarns and
pulled-out fibres
Fig. 7. Typical fabric fracture after subjected to tensile force, (a) whole specimen, (b) magnified fracture area.
Table 8
ANOVA results for hemp fabric mechanical properties.
Sum of squares df Mean square FSig.
ANOVA
Tensile strength Between groups 108.032 3 36.011 8.931 0.000
Within groups 145.161 36 4.032
Total 253.193 39
Tensile strain Between groups 0.013 3 0.004 19.613 0.000
Within groups 0.008 36 0.000
Total 0.021 39
Tensile modulus Between groups 0.013 3 0.004 3.223 0.034
Within groups 0.047 36 0.001
Total 0.059 39
Table 9
Duncan multiple comparison test result for hemp fabric composite; (a) tensile
strength, (b) strain, and (c) tensile modulus.
Fabric NSubset for alpha = 0.05
123
(a) Tensile strength (MPa)
Fabric B – Warp 11 21.975
Fabric A – Warp 10 23.392 23.392
Fabric B – Weft 9 24.833 24.833
Fabric A – Weft 10 26.304
Sig. 0.124 0.118 0.111
(b) Tensile strain
Fabric A – Warp 10 0.074
Fabric B – Warp 11 0.093
Fabric B – Weft 9 0.112
Fabric A – Weft 10 0.121
Sig. 1.000 1.000 0.207
Fabric NSubset for alpha = 0.05
12
(c) Tensile Modulus (GPa)
Fabric B – Weft 9 0.493
Fabric A – Weft 10 0.511 0.511
Fabric B – Warp 11 0.530
Fabric A – Warp 10 0.540
Sig. 0.292 0.091
90 M.I. Misnon et al. / Materials and Design 66 (2015) 82–92

look for more detail on significant differences of each composite
sample within each category.
Table 9 shows Duncan multiple comparison tests for warp and
weft direction of woven hemp fabric composite for all categories of
mechanical properties. While the comparison involved all warp
and weft yarns in both fabrics, the attention should be focused
on the comparison between both fabrics warp as well weft yarns
direction. In terms of tensile strength (Table 9(a)), both warps
and wefts were clustered under group 1 and 3 respectively and this
means the differences between warp and weft yarn tensile
strength is significant. The significant value (Sig.) for warp and
weft are 0.124 and 0.111 respectively, this value is far higher (than
0.05) to denial the differences between their means. Therefore, it
can be concluded that even though the warp and weft yarn is dis-
similar, the tensile strength between the warp and also weft yarns
for both fabric are similar. It does not refute the truth that the dif-
ferences of cellulose content in both fabric contribute to different
tensile strength but might be the differences of cellulose content
between Fabric A and B is just small (67.47% and 64.77% respec-
tively) to contribute a bigger gap in tensile strength.
In terms of tensile strain, Table 9(b) shows the differences
between warp yarn strain for Fabric A and Fabric B is significant
with the p-value of 1.00. However, for weft yarns of both fabrics,
they were clustered under group 3 which means that their differ-
ence is insignificant with the significant value of 0.207. Therefore,
it is true that the difference yarn crimp percentage in warp yarns
could affect the tensile strain while the weft crimps for both fabrics
are recorded similar (refer Table 2).
Similar statistical results with tensile strength were found with
tensile modulus. Tensile modulus of weft yarns for both fabrics
was clustered into group 1 with the significant value of 0.292
which mean that their tensile moduli are insignificantly different.
A similar result with warp yarns for both fabrics was found with
the significant value of 0.091 which denial the differences between
their tensile moduli. Again, similar with the tensile strength, the
influence of cellulose and lignin content in the warp and weft fibre
is too small to give a bigger gap in tensile modulus for both fabrics.
With the proof of statistical method, there are no difference
between Fabric A and B in terms of tensile strengths and tensile
moduli. Both Fabrics presumably could perform similar mechanical
effects and behaviours in warp and weft directions. Therefore, it
can be suggested that both fabrics which come from different
batches can be used in a same batch composite production.
4. Conclusions
The presented detailed characterisation of textile woven hemp
fabrics shows a number of findings, some of which are important
in the prediction and interpretation of the properties of hemp fab-
ric reinforced composites;
Both fabrics possess similar fabric density which is 25 23
(warp weft) and similar fabric thicknesses 0.41 mm.
The average warp and weft yarn size for both fabrics are 90 and
93 respectively.
Yarn crimps percentage in weft direction for both fabrics is 9.3%
but in warp yarn is different for Fabric A and B which is 5.4% and
6.0% respectively.
The measured weight using the calculation for Fabric A and B is
234.80 and 236.67 g/m
2
respectively.
In the thermogravimetric analysis, the highest mass loss rate for
Fabric A was recorded higher than Fabric B which was 1.51%/°C
at 37 °C and 1.38%/°C at 380 °C respectively.
The cellulose contents for Fabric A and Fabric B are determined
as 67.47% and 64.77% respectively while for lignin content are
3.52% and 2.92% respectively.
The density of fibre for Fabric A is slightly higher than Fabric B
which is 1.512 and 1.473 g/cm
3
. The relatively high density of
Fabric A fibres correlate well with their higher cellulose content
than Fabric B.
The total cover factor for both fabric is similar with the K-value
of 0.97 which means that 97% of the fabric sheets are covered by
yarn and it is presumed that the resin could penetrate the
whole fabric systems and wet all the fabric thus produced a
good composite material.
The mechanical properties for both fabrics reflect well with
their physical properties, cellulose as well as lignin contents
that they possessed. However, the inferential statistic has pro-
ven that the differences in their tensile strengths and tensile
moduli are insignificant. That is because of the difference in
their cellulose and lignin contents are just small to affect their
differences in mechanical properties. Therefore, both fabrics
can be used or mix-up in the composite fabrication.
It also can be concluded that the properties of the two batches
of similar nominal quality woven hemp fabric obtained within a
time interval of three months, are most likely not only identical
to a textile point of view; such as they share almost the same fabric
density, yarn size and fabric weight but also similar to an engineer-
ing point of view. Therefore, utilisation of both fabrics can be pre-
sumed to give similar effect and behaviour in their contributions.
Acknowledgement
The authors would like to thank Ministry of Higher Education,
Malaysia and Universiti Teknologi MARA, Malaysia for providing
scholarship to first author on doing this work.
References
[1] Nishino T, Hirao K, Kotera M, Nakamae K, Inagaki H. Kenaf reinforced
biodegradable composite. Compos Sci Technol 2003;63:1281–6.
[2] Mishra S, Tripathy SS, Misra M, Mohanty AK, Nayak SK. Novel eco-friendly
biocomposites: biofiber reinforced biodegradable polyester amide
composites—fabrication and properties evaluation. J Reinf Plast Compos
2002;21:55–70.
[3] Misnon MI, Islam MM, Epaarachchi JA, Lau KT. Potentiality of utilising natural
textile materials for engineering composites applications. Mater Des
2014;59:359–68.
[4] Madsen B, Hoffmeyer P, Thomsen AB, Lilholt H. Hemp yarn reinforced
composites – I. Yarn characteristics. Compos A Appl Sci Manuf
2007;38:2194–203.
[5] Chilton J, Velasco R. Applications of textile composites in the construction
industry. In: Long AC, editor. Design and manufacture of textile
composites. Cambridge, England: CRC Press, Woodhead Publishing Ltd.;
2005. p. 424–35.
[6] Netravali AN, Huang X, Mizuta K. Advanced ‘green’ composites. Adv Compos
Mater 2007;16:269–82.
[7] Satyanarayana KG, Arizaga GGC, Wypych F. Biodegradable composites based
on lignocellulosic fibers—an overview. Prog Polym Sci 2009;34:982–1021.
[8] Akovali G, Uyanik N. Introduction. In: Akovali G, editor. Handbook of
composite fabrication. Shropshire, UK: Rapra Technology Limited; 2001. p.
1–19.
[9] Sondhelm WS. Technical fabric structures – 1. Woven fabrics. In: Horrocks AR,
Anand SC, editors. Handbook of technical textiles. North and South
America: Woodhead Publishing Limited & The Textile Institute; 2000.
[10] Yahya MF, Salleh J, Ahmad WYW. Uniaxial failure resistance of square-
isotropic 3D woven fabric modelled with finite element analysis. Business,
Engineering and Industrial Applications (ISBEIA). In: 2011 IEEE symposium on
2011. p. 16–21.
[11] Huang X, Netravali A. Characterization of flax fiber reinforced soy protein resin
based green composites modified with nano-clay particles. Compos Sci
Technol 2007;67:2005–14.
[12] Süle G. Investigation of bending and drape properties of woven fabrics and the
effects of fabric constructional parameters and warp tension on these
properties. Text Res J 2012;82:810–9.
[13] Chen X, Leaf GAV. Engineering design of woven fabrics for specific properties.
Text Res J 2000;70:437–42.
[14] Ishak MR, Sapuan SM, Leman Z, Rahman MZA, Anwar UMK. Characterization of
sugar palm (Arenga pinnata) fibres. J Therm Anal Calorim 2012;109:981–9.
[15] Yang H, Yan R, Chen H, Lee DH, Zheng C. Characteristics of hemicellulose,
cellulose and lignin pyrolysis. Fuel 2007;86:1781–8.
M.I. Misnon et al. / Materials and Design 66 (2015) 82–92 91

[16] Kabir MM, Wang H, Lau KT, Cardona F. Effects of chemical treatments on hemp
fibre structure. Appl Surf Sci 2013;276:13–23.
[17] Hakamy A, Shaikh FUA, Low IM. Thermal and mechanical properties of hemp
fabric-reinforced nanoclay–cement nanocomposites. J Mater Sci
2014;49:1684–94.
[18] Wang HM, Postle R, Kessler RW, Kessler W. Removing pectin and lignin during
chemical processing of hemp for textile applications. Text Res J
2003;73:664–9.
[19] Le Troedec M, Sedan D, Peyratout C, Bonnet JP, Smith A, Guinebretiere R, et al.
Influence of various chemical treatments on the composition and structure of
hemp fibres. Compos A Appl Sci Manuf 2008;39:514–22.
[20] Bismarck A, Aranberri-Askargorta I, Springer J, Lampke T, Wielage B,
Stamboulis A, et al. Surface characterization of flax, hemp and cellulose
fibers; surface properties and the water uptake behavior. Polym Compos
2002;23:872–94.
[21] Dhakal HN, Zhang ZY, Richardson MOW. Effect of water absorption on the
mechanical properties of hemp fibre reinforced unsaturated polyester
composites. Compos Sci Technol 2007;67:1674–83.
[22] Mohanty, Misra M, Drzal TL, Selke SE, Harte BR, Hinrichsen G. Natural fibers,
biopolymers, and biocomposites: an introduction. CRC Press-Taylor & Francis
Group LLC; 2005. p. 1–36.
[23] Azwa ZN, Yousif BF, Manalo AC, Karunasena W. A review on the
degradability of polymeric composites based on natural fibres. Mater Des
2013;47:424–42.
[24] Sedan D, Pagnoux C, Smith A, Chotard T. Mechanical properties of hemp fibre
reinforced cement: influence of the fibre/matrix interaction. J Eur Ceram Soc
2008;28:183–92.
[25] Faruk O, Bledzki AK, Fink H-P, Sain M. Biocomposites reinforced with natural
fibers: 2000–2010. Prog Polym Sci 2012;37:1552–96.
[26] Dittenber DB, GangaRao HVS. Critical review of recent publications on use of
natural composites in infrastructure. Compos A Appl Sci Manuf
2012;43:1419–29.
[27] Ambroziak A, Kłosowski P. Mechanical testing of technical woven fabrics. J
Reinf Plast Compos 2013;32:726–39.
[28] Christian SJ, Billington SL. Mechanical response of PHB- and cellulose acetate
natural fiber-reinforced composites for construction applications. Compos B
Eng 2011;42:1920–8.
[29] Lomov SV, Verpoest I, Robitaille F. Manufacturing and internal geometry
of textiles. In: Long AC, editor. Design and manufacture of textile
composites. Cambridge, England: CRC Press, Woodhead Publishing Ltd.;
2005. p. 1–61.
92 M.I. Misnon et al. / Materials and Design 66 (2015) 82–92